Combined adjustable orifice and valve



R. w. THOMAS COMBINED ADJUSTABLE ORIFIC AND `VALVE Filed Sept. 19, 1959Nov. 4, 1941.

Patented Nov. 4, 1941 Rosswell W. Thomas, Birmingham, Mich.,assignor toPhillips Petroleum Company, a corporation of Delaware ApplicationSeptember 19, 1939, Serial No. 295,656

2 Claims.

This invention relates to a combined adjustable orifice and valve devicewhich is adapted to be employed in connection with various types of gasconsuming appliances.

The usual air inspirating gas burner is provided with a fixed gasorifice and a closing valve positioned upstream with respect to theorifice, which valve controls and throttles down the gas supply to theburner to meet'the consumers requirements. A partial closure of thevalve reduces the gas pressure on the upstream side of the orifice anddiminishes the velocity of the gas emitted throughthe orice, therebydecreasing the percentage of primary air inspirated. This generally'results in the entralnment of an insuicient amount of primary airnecessary to produce complete combustion in the burner, as

evidenced by a yellow flame condition. Heretofore, only about 60 percent of the air essential for complete combustion has been inspirated asprimary air, any additional or secondary air being obtained from theatmosphere surrounding the burner ports. Experience has shown that thereare substantial losses due to excessive or otherwise improper secondaryaeration resulting in incomplete combustion and oftentimes in theformation of considerable quantities of highly undesirable and extremelydangerous carbon monoxide'.

The practice of my instant invention over- .comes the dimcultiesindicated above and at the for any secondary aeration to operate theburner in a successful and eilicient manner. t

The orifice member may be made of any resilient and readily distortablesubstance. While natural rubber compounds may be employed in someinstances, I nd that these compounds tend to become vulcanized when leftunder compression for appreciable periods of time. Furthermore, naturalrubbers will expand to such an extent when in contact with certain fuelgases including propane, butane,v and mixtures thereof,v that the boreor orice soon becomes completely closed even though no adjustment on theoriiice member is made in the interim. On the other hand, varioussynthetic rubber compositions, such as Neoprene are entirelysatisfactory for use in my present invention. These synthetic rubberswill notl vulcanize in the presence of propane or similar gases; they dobore therethrough for the passage of gas. This` orifice member isassociated with jan air in- 40,

spirating venturi and is provided with means for varying the size of thebore from fully open to completely closed position. It will be readilyapparent from an inspection of the drawing and the detailed descriptionthat the orice member is capable of an infinite range of adjustments andthat it further serves as a valve to control the admission of gas to theburner proper.' The amount of gas admitted to the burner is directlydependent on the size of the bore inthe orifice member at any particulartime. Regardless of not become distorted or enlarged when in contactwith these gases; nor do they apparently lo'se any of their propertiesof resiliency or distortability from continuous normal use in my device.f

It is the primary object of this invention to provide a combinedadjustable orifice and valve device which will emit gas at a constantpressure drop and thereby maintain the primary air inspiratingefficiency of a gas consuming appliance at a high and substantiallyuniform level under various normal operating conditions.

Another object of this invention is to provide a device of the characterindicated wherein an adjustable 'orifice also serves as a closingvalve.`

My invention has for a further object the provision of a combinedadjustable orice and valve device which isadaptable for use with gasconsuming appliances and which is simple and compact in design, andinexpensive to manufacture and maintain.

'I'hese and additional objects and advantages will be readily apparentto those skilled in the art by reference to the following descriptionand annexed drawing which respectively describe and illustrate apreferred embodiment of this invention, and wherein larly to Figure l, Ihave denoted therein a conduit composed of a section ofpillins Il, an L-connector Il, and a tube I2. 'lne conduit il employed to transmit a fuelgas. such as propane, butane, or mixtures thereof under a predeterminedpressure from a suitable source of supply (not shown). The tube I2 isformed at its forward end with an inwardly extending annular shoulder I3containing a central opening I4. A cap I5 having a. duct IE is slidablymounted on the end of tube I2 and is externally threaded at I1 toreceive a rotating adjusting sleeve I8 which is internally threaded atI8. Adjusting sleeve I8 is also internally threaded at 20 to engage witha corresponding threaded portion on tube I2. It will be observed thatadjusting sleeve I8 is differentially threaded at I8 and 20 to controlthe longitudinal movement of cap I5 and sleeve I8 along tube I2. A keyor pin 2I projects into a slot 22 in the cap member to prevent the capfrom turning when the adjusting sleeve is being rotated.

It is to be clearly understood that the present invention is not limitedto the illustrated differential threaded arrangement on the adjustingsleeve for the purpose of moving cap I5. Instead, threads may beprovided only on the forward or cap end of the sleeve with the oppositeend free to rotate on tube I2, but so arranged as to prevent axialmovement of the sleeve while it is being rotated. The peripheral surfaceof sleeve I8 is preferably knurled to permit the operator 4to obtain afirm grip thereon. It is obvious that rotating sleeve I8 may be remotelyoperated by a chain drive, a flexible cable drive, a worm drive, or byany other suitable actuating means commonly known to persons skilled inthe art.

A resilient distortable member 23, which is preferably composed of a gasresistant synthetic rubber compound, is disposed in cap I5 intermediatethe forward end of the cap and shoulder I3. Member 23 is provided withan orifice or passage 24 which places opening I4, and therefore theinterior of tube I2, in communication with duct I6. It is recommendedthat member 23 be cemented to shoulder I3 in order to overcome thepossibility of the gas leaking therebetween.

An air inspirating unit which includes a venturi having a throat portion25 and a flared portion 26 is provided with an inwardly extending flange21, at the center of which is an opening 28 to receive the forward endof cap I5. Flange 21 has a pair of curved air admission ports 29 and isequipped with a shutter 30 having a pair of ports 3| which correspond insize and relative position to ports 29. Shutter 30 is maintained againstiiange 21 by a screw 32 which projects through and beyond a shutteradjustment slot 33. T he interior of the forward portion 34 of theventuri constitutes a pre-mix chamber wherein gas and air admittedthrough duct I 6 and slots 29, respectively, are thoroughly agitated andmixed before being emitted through burner ports 35.

In the practice and operation of my present invention, adjusting sleeveI8 is actuated to slide cap I5 to the left or to the right along tubeI2, depending upon the direction of rotation of the sleeve. The drawingillustrates the relative position of the various parts when adjustingsleeve I8 has been rotated so as to draw cap I5 toward the left, therebycompressing resilient member 23 and reducing the size of orifice orpassage 24. As a consequence, thequantity of gas passing through theconduit, orifice 24, and thence into the air inspirating unit has beencorrespondingly reduced, but there is a constant pressure drop acrossthe distortable member, regardless of the size of the orifice. Adjustingsleeve I8 may be rotated to further restrict the size of opening 24 orpermit resilient member '23 to expand and enlarge orifice 24 in order tomeet the consumers gas requirements. It is evident that a suicientmovement of cap I5 toward the left will distort member 23 to such anextent that orifice 24 will be pinched off or completely closed,distortable member 23 serving at such times as a closing valve. .It isto be understood that the form of my invention, herewith shown anddescribed, is to be taken as a preferred example of the same and thatvarious changes in the shape, size and arrangement of parts may beresorted to Without departing from the spirit of my invention asdel'fined by the appended claims.

I claim:

1. A combined adjustable orifice and valve for use with an airinspirating unit in a gas consuming system comprising a conduit, a capslidably mounted on one end of the conduit, a duct in the cap, aresilient distortable member intermediate the capped end of the conduitand the cap duct, a passage through the distortable member communicatingwith the conduit and the duct, and means cooperating with the cap formoving the same to deform the distortable member, thereby varying thesize of the passage from full open position to closed position.

2. A combined adjustable orifice and valve for use with an airinspirating unit in a gas consuming system comprising a conduit, a capslidably mounted on one end of the conduit, a duct -in the cap, aresilient `distortable member in the cap, a passage through thedistortable member communicating with the conduit and the duct, androtatable means cooperating with the cap for moving the same in alongitudinal direction .to deform the distortable member, therebyvarying the size of the passage from full open position to closedposition.

ROSSWELL W. THOMAS.

